Abstract: A system may include a forward signal path having a forward gain and configured to receive an input signal at an input and generate an output signal at an output as a function of the input signal, a feedback signal path having a feedback gain and coupled between the output and the input, and a control subsystem configured to operate the forward signal path and the feedback signal path in at least two modes comprising a first mode in which the forward gain is a first forward gain and the feedback gain is a first feedback gain and a second mode in which the forward gain is a second forward gain smaller than the first forward gain and the feedback gain is a second feedback gain larger than the first feedback gain. The control subsystem may cause operation in the first mode when signal content is present in the input signal and may cause operation in the second mode when signal content is absent from the input signal.

Abstract: A system may include a Class-D stage comprising a first high-side switch coupled between a supply voltage and a first output terminal of the Class-D stage, a second high-side switch coupled between the supply voltage and a second output terminal of the Class-D stage, a first low-side switch coupled between a ground voltage and the first output terminal, and a second low-side switch coupled between the ground voltage and the second output terminal. The system may also include current sensing circuitry comprising a sense resistor, such that an output current through a load coupled between the first output terminal and the second output terminal causes a first sense voltage proportional to the output current across the sense resistor.

Abstract: A system may include a Class-D stage comprising a first high-side switch coupled between a supply voltage and a first output terminal of the Class-D stage, a second high-side switch coupled between the supply voltage and a second output terminal of the Class-D stage, a first low-side switch coupled between a ground voltage and the first output terminal, and a second low-side switch coupled between the ground voltage and the second output terminal. The system may also include current sensing circuitry comprising a first sense resistor coupled between the first low-side switch and the ground voltage, such that an output current through a load coupled between the first output terminal and the second output terminal causes a first sense voltage proportional to the output current across the first sense resistor when the first low-side switch is activated.

Abstract: A system may include a Class-D stage comprising a first high-side switch coupled between a supply voltage and a first output terminal of the Class-D stage, a second high-side switch coupled between the supply voltage and a second output terminal of the Class-D stage, a first low-side switch coupled between a ground voltage and the first output terminal, and a second low-side switch coupled between the ground voltage and the second output terminal. The system may also include current sensing circuitry comprising a first sense resistor coupled between the first high-side switch and the supply voltage, such that an output current through a load coupled between the first output terminal and the second output terminal causes a first sense voltage proportional to the output current across the first sense resistor when the first high-side switch is activated.

Abstract: A system may include a forward signal path having a forward gain and configured to receive an input signal at an input and generate an output signal at an output as a function of the input signal, a feedback signal path having a feedback gain and coupled between the output and the input, and a control subsystem configured to operate the forward signal path and the feedback signal path in at least two modes comprising a first mode in which the forward gain is a first forward gain and the feedback gain is a first feedback gain and a second mode in which the forward gain is a second forward gain smaller than the first forward gain and the feedback gain is a second feedback gain larger than the first feedback gain. The control subsystem may cause operation in the first mode when signal content is present in the input signal and may cause operation in the second mode when signal content is absent from the input signal.

Abstract: A system has an output and receives an input signal. An operational amplifier has an input, an output and an offset at the input. A switched capacitor network samples the input signal at a switched capacitor frequency. An autozeroing capacitor connected to the input of the operational amplifier captures the offset during an offset capture interval according to an autozeroing frequency. Chopping and autozeroing switches, connected between the autozeroing capacitor and the switched capacitor network, chop the sampled input signal according to a chopping frequency and autozero the captured offset according to the autozeroing frequency. De-chopping switches, connected between the output of the operational amplifier and the output of the system, operate on the output of the operational amplifier at the chopping frequency to chop the autozeroed captured offset and de-chop the chopped sampled input signal processed by the operational amplifier.

Abstract: A method may include operating a single-photon avalanche diode (SPAD) in a first mode to determine a light intensity level associated with the SPAD, operating the SPAD in a second mode wherein a reverse bias voltage is applied in the second mode to bias the SPAD beyond its breakdown voltage, such that the SPAD operates in a detection mode, and determining a magnitude of the bias voltage applied to the SPAD in the second mode based on the light intensity level determined in the first mode.

Abstract: A system has an output and receives an input signal. An operational amplifier has an input, an output and an offset at the input. A switched capacitor network samples the input signal at a switched capacitor frequency. An autozeroing capacitor connected to the input of the operational amplifier captures the offset during an offset capture interval according to an autozeroing frequency. Chopping and autozeroing switches, connected between the autozeroing capacitor and the switched capacitor network, chop the sampled input signal according to a chopping frequency and autozero the captured offset according to the autozeroing frequency. De-chopping switches, connected between the output of the operational amplifier and the output of the system, operate on the output of the operational amplifier at the chopping frequency to chop the autozeroed captured offset and de-chop the chopped sampled input signal processed by the operational amplifier.

Abstract: A method for operating a charge pump having a variable switching frequency may include comparing a target minimum output voltage with an output voltage generated at an output of the charge pump and controlling switching of switches of the charge pump based on the comparison such that the variable switching frequency varies as an output current driven by the charge pump varies.

Abstract: Switching circuits controllable to force an input into a circuit and to sense a responsively produced output in multiple ways to produce different combinations of positive and negative polarities of a desired signal and of sources of offsets and 1/f noise. The switching circuits are controlled in a non-ordered time sequence of different combinations of positive and negative polarities of the sources of the offsets and 1/f noise that spreads their energy to a frequency range above the desired signal frequency band. The non-ordered time sequence leaves the polarity of the desired signal unchanged. Uncorrelated delta-sigma modulators may generate the control signal. A DSP processes a resulting spectrum of a digital domain version of the sensed output to measure residual offsets and 1/f noise and adds to an input present at the DSMs a signal equal in magnitude and opposite in sign to the measured residual offsets and 1/f noise.

Abstract: An analog conditioning circuit and a corresponding method for processing an analog input signal provide a conditioned analog signal for input into an analog processing circuit. The analog conditioning circuit comprises a main signal path between an input for receiving the analog input signal and an output for outputting the conditioned analog signal, wherein the transfer function of the main signal path is constrained by a transfer function requirement associated with the analog processing circuit; and a feedforward signal path comprising a first filtering block configured to attenuate desired frequencies of a first signal derived from the analog input signal to provide a filtered analog signal; wherein the feedforward signal path is configured to input the filtered analog signal into the main signal path such that the filtered analog signal is subtracted from a second signal derived from the analog input signal to provide the conditioned analog signal.

Abstract: Switching circuits controllable to force an input into a circuit and to sense a responsively produced output in multiple ways to produce different combinations of positive and negative polarities of a desired signal and of sources of offsets and 1/f noise. The switching circuits are controlled in a non-ordered time sequence of different combinations of positive and negative polarities of the sources of the offsets and 1/f noise that spreads their energy to a frequency range above the desired signal frequency band. The non-ordered time sequence leaves the polarity of the desired signal unchanged. Uncorrelated delta-sigma modulators may generate the control signal. A DSP processes a resulting spectrum of a digital domain version of the sensed output to measure residual offsets and 1/f noise and adds to an input present at the DSMs a signal equal in magnitude and opposite in sign to the measured residual offsets and 1/f noise.

Abstract: Directional couplers are used to detect forward power delivered by a power amplifier. Mechanisms are provided herein which improve the accuracy of the power detection in the presence of external noise. Accuracy in power detection can be used to simplify the design of the power control loop.

Abstract: In an embodiment, a power amplifier (PA) includes a signal processing path including gain stages to receive a radio frequency (RF) signal and to output an amplified RF signal, sensors coupled to the signal processing path each to sense a characteristic of operation of the PA, and a microcontroller configured to execute instructions and to receive the operation characteristic(s) and to control one or more parameters of the signal processing path responsive this operation characteristic.

Abstract: A model-directed sampling system for automatically delivering a customized feed to a plurality of users from a social media service includes a topic model for mathematically inferring a set of abstract topics from a sample stream of content. Upon receiving a selection of user-relevant topics, a query constructor constructs, and continuously refines, a keyword-based query for each user-selected topic. A filter manager then directly interfaces with the social media service and applies the topic queries to a full, continuous media stream. If necessary, the filter manager distributes each topic query across a bank of filters to yield a plurality of individual output streams that are feed rate compliant. By subsequently merging the output streams together, while removing duplicate and/or non-relevant content, a comprehensive yet focused stream of user-relevant content is provided that complies with query requirements established by the social media service.

Abstract: In one embodiment, a power amplifier may include a bridge configuration having a first pair of gain transistors to receive a first portion of a differential signal and to amplify the first portion of the differential signal to an amplified first differential signal portion and a second pair of gain transistors to receive a second portion of the differential signal and to amplify the second portion of the differential signal to an amplified second differential signal portion. This second pair of gain transistors can be configured to be enabled in a first power mode and to be disabled in a second power mode.

Abstract: Embodiments are directed to capacitance compensation via a compensation device coupled to a gain device to compensate for a capacitance change occurring due to an input signal change, along with a controller coupled to the compensation device to receive the input signal and to control an amount of compensation based on the input signal. In some embodiments, banks may be formed of multiple compensation devices, where each of the banks has a different size and is coupled to receive a different set of bias voltages.

Abstract: In one embodiment, the present invention includes a transformer formed on a semiconductor die. Such transformer may have multiple coils, including first and second coils. Each coil may have segments that in turn are formed on a corresponding metal layer of the semiconductor die. The segments of a given coil are coupled to each other, and the first and second coils can be interdigitated with each other.

Abstract: In one embodiment, the present invention includes a transformer formed on a semiconductor die. Such transformer may have multiple coils, including first and second coils. Each coil may have segments that in turn are formed on a corresponding metal layer of the semiconductor die. The segments of a given coil are coupled to each other, and the first and second coils can be interdigitated with each other.

Abstract: In an embodiment, a power amplifier (PA) includes a signal processing path including gain stages to receive a radio frequency (RF) signal and to output an amplified RF signal, sensors coupled to the signal processing path each to sense a characteristic of operation of the PA, and a microcontroller configured to execute instructions and to receive the operation characteristic(s) and to control one or more parameters of the signal processing path responsive this operation characteristic.